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1.
Ann Nucl Med ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39044048

RESUMO

Differentiated thyroid cancer (DTC) is the most common endocrine malignancy. Patients who receive systematic care typically have a better prognosis. RAI treatment plays a key role in eradicating any remaining thyroid lesions in DTC patients, hence decreasing the risk of distant metastases and cancer recurrence. As research continues to advance, RAI treatment is becoming more and more individualized. Because of the excellent prognosis for DTC patients, there is a relatively broad window for RAI treatment, making it easy to overlook when to receive RAI treatment. However, research on this issue can help patients with varying recurrence risk stratification make better decisions about when to begin RAI treatment following surgery, and physicians can schedule patients based on the severity of their disease. This will improve patient prognosis and lessen needless anxiety in addition to helping solve the problems of unjust healthcare resource distribution. In this review, we will mainly discuss the target population of RAI treatment as well as studies that examine the impact of RAI treatment timing on patient outcomes. In an effort to discourage DTC patients and physicians from selecting RAI therapy at random, we also review the possible negative effects of this treatment.

2.
J Am Chem Soc ; 145(28): 15600-15610, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37418344

RESUMO

Single-atom catalysts with a well-defined metal center open unique opportunities for exploring the catalytically active site and reaction mechanism of chemical reactions. However, understanding of the electronic and structural dynamics of single-atom catalytic centers under reaction conditions is still limited due to the challenge of combining operando techniques that are sensitive to such sites and model single-atom systems. Herein, supported by state-of-the-art operando techniques, we provide an in-depth study of the dynamic structural and electronic evolution during the electrochemical CO2 reduction reaction (CO2RR) of a model catalyst comprising iron only as a high-spin (HS) Fe(III)N4 center in its resting state. Operando 57Fe Mössbauer and X-ray absorption spectroscopies clearly evidence the change from a HS Fe(III)N4 to a HS Fe(II)N4 center with decreasing potential, CO2- or Ar-saturation of the electrolyte, leading to different adsorbates and stability of the HS Fe(II)N4 center. With operando Raman spectroscopy and cyclic voltammetry, we identify that the phthalocyanine (Pc) ligand coordinating the iron cation center undergoes a redox process from Fe(II)Pc to Fe(II)Pc-. Altogether, the HS Fe(II)Pc- species is identified as the catalytic intermediate for CO2RR. Furthermore, theoretical calculations reveal that the electroreduction of the Pc ligand modifies the d-band center of the in situ generated HS Fe(II)Pc- species, resulting in an optimal binding strength to CO2 and thus boosting the catalytic performance of CO2RR. This work provides both experimental and theoretical evidence toward the electronic structural and dynamics of reactive sites in single-Fe-atom materials and shall guide the design of novel efficient catalysts for CO2RR.

3.
Drug Dev Res ; 84(6): 1114-1126, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37154105

RESUMO

Our previous work reported that galaxamide, a cyclopeptide extracted from the seaweed Galaxaura filamentosa, showed antiproliferative activity against HeLa cells by MTT assay. In this study, the growth-inhibitory effects of galaxamide in HeLa cells and xenograft mouse models were investigated. It was found galaxamide significantly inhibited cell growth, colony formation, migration, and invasion and induced cell apoptosis by inhibiting the Wnt signaling pathway in HeLa cells. RNA sequencing revealed that galaxamide regulated stemness by Wnt6 signaling pathway in HeLa cells. By analyzing The Cancer Genome Atlas database, Wnt6 was found to be negatively/positively correlated with stemness- and apoptosis-related genes in human cervical cancer. Cancer stem-like cells (CSCs) isolated and enriched from HeLa cells demonstrated elevated Wnt6 and ß-catenin genes compared with nonstem HeLa cells. After galaxamide treatment, CSCs showed abrogation of sphere-forming ability, along with inhibition of stemness-related and Wnt pathway genes. Galaxamide treatment was also accompanied by the induction of apoptosis in HeLa cells, which was consistent with the results in BALB/c nude mice. Our results provide evidence that suppression of stemness by downregulating the Wnt signaling pathway is the molecular mechanism by which galaxamide effectively inhibits cell growth and induces apoptosis in cervical cancer cells.


Assuntos
Neoplasias do Colo do Útero , Via de Sinalização Wnt , Feminino , Humanos , Animais , Camundongos , Células HeLa , beta Catenina/genética , Neoplasias do Colo do Útero/genética , Camundongos Nus , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Apoptose , Proliferação de Células , Linhagem Celular Tumoral
4.
Proc Biol Sci ; 290(1992): 20222014, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36722078

RESUMO

The principal animal lineages (phyla) diverged in the Cambrian, but most diversity at lower taxonomic ranks arose more gradually over the subsequent 500 Myr. Annelid worms seem to exemplify this pattern, based on molecular analyses and the fossil record: Cambrian Burgess Shale-type deposits host a single, early-diverging crown-group annelid alongside a morphologically and taxonomically conservative stem group; the polychaete sub-classes diverge in the Ordovician; and many orders and families are first documented in Carboniferous Lagerstätten. Fifteen new fossils of the 'phoronid' Iotuba (=Eophoronis) chengjiangensis from the early Cambrian Chengjiang Lagerstätte challenge this picture. A chaetal cephalic cage surrounds a retractile head with branchial plates, affiliating Iotuba with the derived polychaete families 'Flabelligeridae' and Acrocirridae. Unless this similarity represents profound convergent evolution, this relationship would pull back the origin of the nested crown groups of Cirratuliformia, Sedentaria and Pleistoannelida by tens of millions of years-indicating a dramatic unseen origin of modern annelid diversity in the heat of the Cambrian 'explosion'.


Assuntos
Anelídeos , Poliquetos , Animais , Estro , Fósseis , Temperatura Alta
5.
Front Endocrinol (Lausanne) ; 13: 950105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36004354

RESUMO

Polycystic ovary syndrome (PCOS) exerts negative effects on females of childbearing age. It is important to identify more suitable models for fundamental research on PCOS. We evaluated animal models from a novel perspective with the aim of helping researchers select the best model for PCOS. RNA sequencing was performed to investigate the mRNA expression profiles in the ovarian tissues of mice with dehydroepiandrosterone (DHEA) plus high-fat diet (HFD)-induced PCOS. Meanwhile, 14 datasets were obtained from the Gene Expression Omnibus (GEO), including eight studies on humans, three on rats and three on mice, and genes associated with PCOS were obtained from the PCOSKB website. We compared the consistency of each animal model and human PCOS in terms of DEGs and pathway enrichment analysis results. There were 239 DEGs shared between prenatally androgenized (PNA) mice and PCOS patients. Moreover, 1113 genes associated with PCOS from the PCOSKB website were identified among the DEGs of PNA mice. A total of 134 GO and KEGG pathways were shared between PNA mice and PCOS patients. These findings suggest that the PNA mouse model is the best animal model to simulate PCOS.


Assuntos
Síndrome do Ovário Policístico , Animais , Desidroepiandrosterona , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/genética , Ratos , Virilismo
6.
Front Oncol ; 12: 830908, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35299734

RESUMO

Background: Ovarian cancer (OC) is one of the most lethal gynecologic malignancies and a leading cause of death in the world. Thus, this necessitates identification of prognostic biomarkers which will be helpful in its treatment. Methods: The gene expression profiles from The Cancer Genome Atlas (TCGA) and GSE31245 were selected as the training cohort and validation cohort, respectively. The Kaplan-Meier (KM) survival analysis was used to analyze the difference in overall survival (OS) between high and low RB transcriptional corepressor 1 (RB1) expression groups. To confirm whether RB1 was an independent risk factor for OC, we constructed a multivariate Cox regression model. Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enrichment analyses were conducted to identify the functions of differentially expressed genes (DEGs). The associations of RB1 with immune infiltration and immune checkpoints were studied by the Tumor Immune Estimation Resource (TIMER 2.0) and the Gene Expression Profiling Interactive Analysis (GEPIA). The immunohistochemistry (IHC) was performed to compare the expression level of RB1 in normal tissues and tumor samples, and to predict the prognosis of OC. Results: The KM survival curve of the TCGA indicated that the OS in the high-risk group was lower than that in the low-risk group (HR = 1.61, 95% CI: 1.28-2.02, P = 3×10-5), which was validated in GSE31245 (HR = 4.08, 95% CI: 1.21-13.74, P = 0.01) and IHC. Multivariate Cox regression analysis revealed that RB1 was an independent prognostic biomarker (HR = 1.66, 95% CI: 1.31-2.10, P = 2.02×10-5). Enrichment analysis suggested that the DEGs were mainly involved in cell cycle, DNA replication, and mitochondrial transition. The infiltration levels of fibroblast, neutrophil, monocyte and macrophage were positively correlated with RB1. Furthermore, RB1 was associated with immune checkpoint molecules (CTLA4, LAG3, and CD274). The IHC staining revealed higher expression of RB1 in tumor tissues as compared to that in normal tissues (P = 0.019). Overexpression of RB1 was associated with poor prognosis of OC (P = 0.01). Conclusion: These findings suggest that RB1 was a novel and immune-related prognostic biomarker for OC, which may be a promising target for OC treatment.

7.
Chem Commun (Camb) ; 58(8): 1135-1138, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34981092

RESUMO

A Ni/(S,S)-BDPP-catalyzed intramolecular Heck cyclization of N-(2-iodo-aryl) acrylamide with 2-methyl-2-phenylmalononitrile was developed to give oxindoles with good enantioselectivities. We found that utilizing such an electrophilic cyanation reagent could tackle the deleterious effect of the coordinative cyanide ion in the asymmetric alkene arylcyanation.

8.
Front Immunol ; 12: 613365, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149681

RESUMO

Hyla annectans is a tree frog living in the southwestern plateau area of China where there is strong ultraviolet radiation and long duration of sunshine. So their naked skin may possess chemical defense components that protect it from acute photo-damage. However, no such peptide or components has been identified till to date. In the current work, two novel peptides (FW-1, FWPLI-NH2 and FW-2, FWPMI-NH2) were identified from the skin of the tree frog. Five copies of FW-1 and four copies of FW-2 are encoded by an identical gene and released from the same protein precursor, which possess 167 amino acid residues. FW-1 and -2 can exert significant anti-inflammatory functions by directly inhibiting Ultraviolet B irradiation (UVB)-induced secretion of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). They may achieve this function by modulating the UV-induced stress signaling pathways such as Mitogen-activated protein kinases (MAPK) and Nuclear Factor Kappa B (NF-κB). Besides, FW-1 and -2 showed potential antioxidant effects on epidermis by attenuating the UVB-induced reactive oxygen species (ROS) production through an unknown mechanism. Considering small peptides' easy production, storage, and potential photo-protective activity, FW-1/2 might be exciting leading compounds or templates for the development of novel pharmacological agents for the suppression of UVB-induced skin inflammation. Moreover, this study might expand our knowledge on skin defensive mechanism of tree frog upon UVB irradiation.


Assuntos
Proteínas de Anfíbios/metabolismo , Anti-Inflamatórios/metabolismo , Queratinócitos/fisiologia , Peptídeos/metabolismo , Pele/metabolismo , Raios Ultravioleta/efeitos adversos , Proteínas de Anfíbios/genética , Animais , Antioxidantes , Anuros , China , Clonagem Molecular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Peptídeos/genética , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Pele/patologia , Fator de Necrose Tumoral alfa/metabolismo
9.
Nat Cell Biol ; 23(3): 268-277, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33664495

RESUMO

The sympathetic nervous system-catecholamine-uncoupling protein 1 (UCP1) axis plays an essential role in non-shivering adaptive thermogenesis. However, whether there exists a direct effector that physically connects catecholamine signalling to UCP1 in response to acute cold is unknown. Here we report that outer mitochondrial membrane-located AIDA is phosphorylated at S161 by the catecholamine-activated protein kinase A (PKA). Phosphorylated AIDA translocates to the intermembrane space, where it binds to and activates the uncoupling activity of UCP1 by promoting cysteine oxidation of UCP1. Adipocyte-specific depletion of AIDA abrogates UCP1-dependent thermogenesis, resulting in hypothermia during acute cold exposure. Re-expression of S161A-AIDA, unlike wild-type AIDA, fails to restore the acute cold response in Aida-knockout mice. The PKA-AIDA-UCP1 axis is highly conserved in mammals, including hibernators. Denervation of the sympathetic postganglionic fibres abolishes cold-induced AIDA-dependent thermogenesis. These findings uncover a direct mechanistic link between sympathetic input and UCP1-mediated adaptive thermogenesis.


Assuntos
Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/inervação , Proteínas de Transferência de Fosfolipídeos/metabolismo , Sistema Nervoso Simpático/fisiologia , Termogênese , Proteína Desacopladora 1/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Animais , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Metabolismo Energético , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxirredução , Proteínas de Transferência de Fosfolipídeos/deficiência , Proteínas de Transferência de Fosfolipídeos/genética , Fosforilação , Transdução de Sinais , Proteína Desacopladora 1/deficiência , Proteína Desacopladora 1/genética
10.
Angew Chem Int Ed Engl ; 59(2): 798-803, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31657106

RESUMO

Designing effective electrocatalysts for the carbon dioxide reduction reaction (CO2 RR) is an appealing approach to tackling the challenges posed by rising CO2 levels and realizing a closed carbon cycle. However, fundamental understanding of the complicated CO2 RR mechanism in CO2 electrocatalysis is still lacking because model systems are limited. We have designed a model nickel single-atom catalyst (Ni SAC) with a uniform structure and well-defined Ni-N4 moiety on a conductive carbon support with which to explore the electrochemical CO2 RR. Operando X-ray absorption near-edge structure spectroscopy, Raman spectroscopy, and near-ambient X-ray photoelectron spectroscopy, revealed that Ni+ in the Ni SAC was highly active for CO2 activation, and functioned as an authentic catalytically active site for the CO2 RR. Furthermore, through combination with a kinetics study, the rate-determining step of the CO2 RR was determined to be *CO2 - +H+ →*COOH. This study tackles the four challenges faced by the CO2 RR; namely, activity, selectivity, stability, and dynamics.

11.
Exp Eye Res ; 145: 352-358, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26919788

RESUMO

Uncontrolled activation of complement and upregulation of vascular endothelial growth factor (VEGF) play fundamental roles in age-related macular degeneration (AMD). However, most drugs used to treat AMD focus on a single target, and the percentage of effectively treated patients in clinical practice needs to be improved. Therefore, novel AMD treatment approaches are needed. IBI302 is a novel bispecific decoy receptor fusion protein designed with both a VEGF inhibition domain and a complement cascade inhibition domain, which are connected by the Fc region of human immunoglobulin. In this study, we systematically evaluated the binding affinity between IBI302 and VEGF isoforms and complement proteins by using surface plasmon resonance (SPR) technology. Anti-VEGF blockers (aflibercept and bevacizumab) and complement receptor 1 were used as references. The SPR assay results indicated that IBI302 could bind different VEGF isoforms and complement proteins with high affinity. The biological activity of IBI302 was also studied. IBI302 showed an inhibitory effect on human primary umbilical vein endothelial cell proliferation and the activation of complement pathways in vitro. Finally, the pharmacokinetic (PK) properties of IBI302 were evaluated in rhesus monkeys. The PK results showed that after a 0.5 mg/eye intravitreal dosage, IBI302 became rapidly distributed from the vitreous humor into targeted tissues and remained active over 504 h. Overall, the favorable anti-angiogenic and anti-complement effects of IBI302 along with the good PK profiles in rhesus monkeys support the selection and development of IBI302 as a promising candidate for AMD treatment.


Assuntos
Inibidores da Angiogênese/farmacologia , Ativação do Complemento/efeitos dos fármacos , Inativadores do Complemento/farmacologia , Fragmentos Fc das Imunoglobulinas/farmacologia , Degeneração Macular/tratamento farmacológico , Proteínas Recombinantes de Fusão/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores da Angiogênese/farmacocinética , Animais , Anticorpos Monoclonais Humanizados/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Inativadores do Complemento/farmacocinética , Proteínas do Sistema Complemento/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Injeções Intravítreas , Macaca mulatta , Proteínas Recombinantes de Fusão/farmacocinética , Corpo Vítreo/metabolismo
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